1. Field
The following description relates generally to a touch screen, and more particularly to a method of manufacturing a transparent circuit substrate for a touch screen. The transparent circuit substrate may include an electrode layer, and it may form a front surface of a touch screen.
2. Description of the Related Art
In general, a touch screen refers to a device where an input detection unit is integrated with a display unit. A touch screen may include, for example, a display unit such as a liquid crystal display (LCD) along with a touch panel disposed on such a display unit.
When a finger tip of a user or another object contacts a letter or a specific location displayed on such a touch screen, the touch screen may be configured to recognize the location and receive an input of the user through a screen contact without the use of a mechanical keypad.
Such touch screens usually do not show high precision. However, they are widely used as a guide display device in places generally used by the public, for example, as in public places such as subways, department stores, and banks. This is because it is simple to manipulate such touch screens to input information. Further, touch screens are widely used in sales terminals of various stores. In recent years, touch screens are also widely used in portable terminals such as mobile phones, DMB (Digital Multimedia Broadcasting) receivers, and vehicle navigation systems.
Some examples of touch screens (or touch panels) include a resistive overlay type touch screen, a capacitive overlay type touch screen, a surface acoustic wave type touch screen, and an infrared beam type touch screen.
In a typical capacitive overlay type touch screen, the first and second electrode layers are usually formed on the first and second films, respectively. The first film is usually bonded to an upper glass substrate that forms a front surface of the touch screen. The second film is usually bonded to a lower substrate. The first and second electrode layers are usually connected to a control unit via connecting terminals. The control unit may detect a change in the electrostatic capacitance at a corresponding part of the touch panel in response to a contact by an input device such as a stylus pen, a finger, and the like.
However, since the conventional capacitive overlay type touch screen includes a plurality of films, it usually has a large thickness with a low light transmission.
As a material having a high transmission is usually used as the films for the touch screen, an entire light transmission from the touch screen cannot be transmitted to the user. Rather, because the light transmission of each film is less than 100%, the light transmission of the touch screen is reduced as the number of the films inside the touch screen increases.
Since a conventional capacitive overlay type touch screen typically includes a plurality of films, the touch screen usually has a large thickness and a low light transmission. The low light transmission degrades the visibility of the screen, and it is also difficult to reduce the overall thickness of a product containing such a touch screen.